Multiply. $0.64 \times 5.3=$
Solution: $64 \times 53$ and $0.64\times 5.3$ multiply the same digits in the same order. So, the product of both problems will also have the same digits in the same order. Let's multiply $64 \times 53$. Then we can estimate to place the decimal point in the product of $0.64\times 5.3$. $\begin{aligned} 64&\\ \underline{ \times 53}&\\ 12}& {3} \times{4\text{ ones}}\\ 180}& {3} \times{6\text{ tens}}\\ 200}& {50} \times {4\text{ ones}}\\ \underline{+3{,}000}}& {50} \times {6\text{ tens}}\\ 3{,}392 \end{aligned}$ Let's estimate to place the decimal in $0.64 \times 5.3$. $\begin{aligned} 0.64\times 5.3 &\approx 1\times 5\\\\ &\approx 5 \end{aligned}$ Where can we place the decimal in $3{,}392$ to get a product close to $5$ ? $0.64\times5.3=3.392$